The invention relates to a connecting element for the releasable connection of two structural parts of stands, in particular a support section and a frame section, wherein the connecting element is mounted stationarily in a hollow frame section and comprises a housing having therein at least one locking element, whereby the connecting element and thus the frame section may be connected releasably with the support section. In the housing of the connecting element an eccentric is rotatingly supported, whereby the locking element is guided in a longitudinally mobile manner in the housing and whereby a structural part protruding from the front side of the housing of the locking element may be introduced into an undercut groove of the support section and tightly clamped therein. An eccentric head of the eccentric is insertable into the housing and may be locked in a bore hole of the frame section.
Connecting elements of this type are known in numerous configurations and are used in particular for the joining of support sections and frame sections, whereby structures such as, exhibition stands are erected. This connection should be extremely strong, but also readily produceable and releasable.
A connecting element of this generic type is known from DE-OS No. 31 28 595, corresponding to U.S. Pat. No. 4,455,103. This connecting element consists of a bearing housing with a rising wedge surface and a locking element contained therein in a longitudinally displaceable manner and in the form of a strip of sheet metal and provided with a counter bevel pressed by the force of a spring against the wedge surface. By means of an eccentric the locking element in the form of a sheet metal strip may be moved longitudinally, whereby a joining hook on the end side of the locking element is displaceable both longitudinally and, by motion of the counter bevel on the wedge surface, also transversely. A spring tongue is cut from metal strip and bent down, with the end of such tongue being supported on an inner wall of the bearing housing and longitudinally guided thereon. The wedge surface extends between two joining projections and is overlapped by a bend of the holding element, which secures the eccentric bolt in a rear wall recess of the bearing housing.
A connecting element of this type is not only difficult to assemble, but there are considerable difficulties involved in its application, since if the locking element is tightened severely by means of the eccentric, the holding element loses contact with the wedge surface and the connection may be released. In addition, if the connecting element is stressed strongly as the result of the one-sided pressing of the joining hook on the undercut groove of the support section, the connecting element may be tilted, leading to problems in the assembly of, for example, an exhibition booth and in case of a heavy load the connection may be released unintentionally.